Validations ensure data consistency before persisting to the database, catching invalid states early in the request lifecycle. I combine presence validations for required fields, uniqueness constraints that map to database indexes, and format validati

Unbounded network calls eventually will hang, and then your Node process gets stuck with slow requests chewing up the connection pool. I wrap fetch with an AbortController timeout so every outbound call has an upper bound. The key is distinguishing be

Interactive UI should feel instant even when the network isn’t. With optimistic updates, I update the cache immediately and roll back if the server rejects the mutation. The trick is to keep optimistic state small and obvious: update a count and a boo

Recurring tasks like cleanup jobs, report generation, or cache warming need reliable scheduling. The sidekiq-scheduler gem extends Sidekiq with cron-like scheduling without requiring separate infrastructure like cron or Kubernetes CronJobs. I define s

Wizards are often over-engineered with client state machines. With Turbo Frames, I render each step inside a frame, and the “Next” button simply POSTs to update the record and then redirects to the next step URL. If validation fails, I re-render the s

After a successful inline create, I usually want to clear the form. You can replace the whole form partial, but sometimes you want to preserve other state (like which field was focused) and simply reset values. A clean Hotwire approach is a custom Tur

A single abusive client can ruin your latency budget for everyone else, so I rate limit early rather than trying to ‘detect abuse’ after the outage starts. I combine an IP bucket with a user bucket: IP protects unauthenticated endpoints, user protects

Soft deletes mark records as deleted without removing them from the database. I add a deleted_at field and override the delete() method. A custom manager excludes soft-deleted records by default. I provide a hard_delete() method for permanent removal.

Long-running requests tie up worker threads and degrade overall application responsiveness. Rack::Timeout enforces request timeouts at the Rack layer, killing requests that exceed configured limits. I set conservative timeouts (15-30 seconds) and hand

If a hot key expires, you can stampede your DB. race_condition_ttl lets one process recompute while others serve stale content briefly. This is a reliability pattern masquerading as caching.

Celery Beat schedules periodic tasks like cron jobs. I define schedules in settings or use the Django database scheduler. Tasks run at specified intervals or cron expressions. I use @periodic_task decorator or configure in CELERY_BEAT_SCHEDULE. For dy

Indexes dramatically improve query performance. I add indexes via Meta.indexes or db_index=True on frequently-filtered fields. Compound indexes help queries filtering on multiple fields. For text search, I use GinIndex on PostgreSQL. I index foreign k